SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2019, Vol. 27 ›› Issue (5): 1050-1057.DOI: 10.1016/j.cjche.2018.09.012

• Separation Science and Engineering • 上一篇    下一篇

Mechanism and kinetics study on removal of Iron from phosphoric acid by cation exchange resin

Xinke Leng, Yanjun Zhong, Dehua Xu, Xinlong Wang, Lin Yang   

  1. School of Chemical Engineering, Sichuan University, Chengdu 610065, China
  • 收稿日期:2018-06-25 修回日期:2018-09-03 出版日期:2019-05-28 发布日期:2019-06-27
  • 通讯作者: Lin Yang
  • 基金资助:
    Supported by the National Basic Research Program of China (2016YFD0200404).

Mechanism and kinetics study on removal of Iron from phosphoric acid by cation exchange resin

Xinke Leng, Yanjun Zhong, Dehua Xu, Xinlong Wang, Lin Yang   

  1. School of Chemical Engineering, Sichuan University, Chengdu 610065, China
  • Received:2018-06-25 Revised:2018-09-03 Online:2019-05-28 Published:2019-06-27
  • Contact: Lin Yang
  • Supported by:
    Supported by the National Basic Research Program of China (2016YFD0200404).

摘要: Iron element is one of the main impurities in wet-process phosphoric acid and it has a significant impact on the subsequent phosphorus chemical products. This paper studied the feasibility of using Sinco-430 cation exchange resin for iron removal from phosphoric acid. The specific surface area and the total exchange capacity of resin were 8.91 m2·g-1 and 5.18 mmol·g-1, respectively. The sorption mechanism was determined by FTIR and XPS and the results indicated that iron was combined with—SO3H in resin. The removal process was studied as a function of temperature, H3PO4 content and mass ratio between resin and solution. The unit mass of resin to remove iron was 0.058 g·g-1 resin when the operating parameters were T=50℃, H3PO4 content=27.61 wt% and S/L=0.1, respectively. Kinetics study demonstrated that pseudo-second-order reaction model fits this study best and the calculated activation energy of overall reaction is 29.10 kJ·mol-1. The overall reaction process was mainly controlled by pore diffusion.

关键词: Purification of wet-process phosphoric acid, Cation exchange resin, Kinetics models, Diffusion models

Abstract: Iron element is one of the main impurities in wet-process phosphoric acid and it has a significant impact on the subsequent phosphorus chemical products. This paper studied the feasibility of using Sinco-430 cation exchange resin for iron removal from phosphoric acid. The specific surface area and the total exchange capacity of resin were 8.91 m2·g-1 and 5.18 mmol·g-1, respectively. The sorption mechanism was determined by FTIR and XPS and the results indicated that iron was combined with—SO3H in resin. The removal process was studied as a function of temperature, H3PO4 content and mass ratio between resin and solution. The unit mass of resin to remove iron was 0.058 g·g-1 resin when the operating parameters were T=50℃, H3PO4 content=27.61 wt% and S/L=0.1, respectively. Kinetics study demonstrated that pseudo-second-order reaction model fits this study best and the calculated activation energy of overall reaction is 29.10 kJ·mol-1. The overall reaction process was mainly controlled by pore diffusion.

Key words: Purification of wet-process phosphoric acid, Cation exchange resin, Kinetics models, Diffusion models